package com.hmdp.utils;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

/**
 * ClassName: RedisIdWorker
 * Package: com.hmdp.utils
 * Description:
 *
 * @Author BuTang
 * @Create 2024/2/21 14:05
 * @Version 1.0
 */
@Component
public class RedisIdWorker {
    @Resource
    private StringRedisTemplate stringRedisTemplate;

    //开始的时间戳
    private static final long BEGIN_TIMESTAMP = 1640995200L;

    //序列号的位数
    private static final int COUNT_BITS = 32;

    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }
    public long nextId(String keyPrefix){
        // 1. 生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timeStamp = nowSecond - BEGIN_TIMESTAMP ;

        // 2. 获取序列号
        // 2.1 获取当前日期，精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        // 2.2 自增长
        Long count = stringRedisTemplate.opsForValue().increment("icr" + keyPrefix + ":" + date);

        return  timeStamp << COUNT_BITS | count;
    }


}
